1. Field of the Invention
This application claims priority to Taiwanese Application No. 99137901, filed on Nov. 4, 2010, which is incorporated by reference in its entirety.
The present invention relates to positioning techniques in the field of wireless communication, and, more particularly, to a method and system that use a SUPL platform and a network system supporting the SUPL platform to position a femtocell base station such as a femtocell base station.
2. Description of Related Art
In the development of network communications, network coverage has long been a focus of concern for Internet service providers and an important factor considered by users when choosing Internet service providers. Currently, the coverage of wide area networks is quite stable. For example, the coverage of macrocell base stations can reach sparsely populated regions and fast moving users and even remote villages. But in the buildings of densely populated cities, the macrocell coverage can be quite poor. Accordingly, femtocell base stations have been developed to extend the coverage of mobile networks so as to overcome the above-described drawback of poor indoor coverage.
Similar to a macrocell base station, a femtocell base station in operation needs to provide its geographical location information to a core network for registration so as to facilitate management of mobile network deployment, and further needs to continuously broadcast its geographical location information within its coverage such that, when a mobile communication terminal such as a mobile phone enters into the coverage of the femtocell base station, it can receive the geographical location information so as to establish a wireless network connection for wireless communication. Therefore, to enable the femtocell base station to provide communication services, a positioning process needs to be performed.
Currently, the positioning of femtocell base stations depends on conventional global navigation satellite system (GNSS) chips/receivers. For example, a femtocell base station has a GNSS chip/receiver disposed therein for calculating positioning data (for example, differential correction data, satellite running state, etc.) so as to capture GNSS signals for positioning. However, such a positioning method is often limited by the GNSS chip/receiver sensitivity and signal strength, thereby resulting in the problem that it takes a long time for a first time positioning or positioning cannot be performed. Alternatively, a femtocell base station can have an assisted global navigation satellite system (A-GNSS) chip/receiver disposed therein for receiving assistant positioning information from an A-GNSS server through Internet connection so as to quickly capture signals Such a positioning method shortens the time for a first time positioning, but positioning still cannot be performed in an environment where GNSS signals are weak, for example, when the GNSS signals are blocked by clouds or buildings.